Hi everybody!
I can't explain this...I've read all the topics about removing margins on pdf in the forum, I've tried sopdf and it worked great. Everything is perfect, but when I put the modified pdf (with all the margins cropped) into my kindle 2 with calibre, I'm still viewing all the margin on my kindle screen! Why? Also tried the little hack of HORIZONTAL_MARGIN on the reader.pref file as explained here (http://wiki.mobileread.com/wiki/Kindle_HowTo:_Change_Margin), but nothing changed for pdfs.

Thanks for your precious help!

The kindle 2&3 automatically crop the margins and auto-fit the PDF for you, so tools like soPDF don't help much, unless you us them to modify the layout.

What is happening is the PDF you are modifying is too tall for the kindle screen so as the shrinks the page the margin increase. soPDF has a feature to maximize the width and concatinate the hieght

I have tried the same thing with BRISS. But even thought the margins are cut, the Kindle itself adds them while viewing. I don't know why they have this useless feature.

Kindle will already crop whitespace in fit-to-screen or fit-to-width zoom mode. So there's not much to be gained by cropping the whitespace only - unless you are using the other zoom modes, which do not auto-crop whitespace.

Where cropping adds value is when you crop the (more or less redundant) headers and footers. Then the content you are interested in reading can be zoomed in further and can usually utilize more of Kindle's limited real estate (depending on the relative aspect ratio of the document and Kindles viewing area).

The Kindle PDF viewer establishes fixed margins of 25 pixels on left, top, and right sides, and 55 pixels on the bottom (where reading progress is shown). In general the margins are larger than this on left/right because the aspect ratio of the document is usually 'taller' than that of the viewing area. It would be nice if there were a full-screen mode that dispensed with all or most of these fixed margins along with the reading progress, but PDF viewing of (mostly) letter or A4 size documents on Kindle's much smaller screen is never going to be ideal.

try using the landscape mode when reading your cropped PDFs (set to "fit-to-width")

The kindle 2&3 automatically crop the margins and auto-fit the PDF for you, so tools like soPDF don't help much, unless you us them to modify the layout.

What is happening is the PDF you are modifying is too tall for the kindle screen so as the shrinks the page the margin increase. soPDF has a feature to maximize the width and concatinate the hieght

Wonderful! It works now, using "fix2x height" options on sopdf (plus reverse landscape). Yes, each pdf is different from one other, and the A4 size it's not the best for kindle screen. But sometimes conversions are worst then cropping pages in two parts.

Thanks a lot :-)

I used this tool - Pdf Scissors (http://www.pdfscissors.com/) to cut the pdf margins for kindle. It's quite cool.